I'm not sure about the mall- if you're able to position the baby where you feel comfortably covered (I know when you are first learning to latch and everything sometimes you have to practically strip!) then you could just sit on a bench or in one of those massage chair things, etc. Or you could pop into a dressing room for a little while- Mothering or other maternity stores will usually let you go in if you tell them you need to nurse for awhile.
A great restaurant that I've had nursing success in is Paul's in Elgin. My friends and I nurse (even our toddlers) there all the time. Gail Borden Public Library is very nursing-friendly too and has really comfy chairs in the cafe part and rockers in the kids' section.
I have a 15 month old nursling and would be happy to meet you somewhere if you'd like company (we live in Elgin) or you're also more than welcome to join the AP group that I co-own with a friend:
http://groups.yahoo.com/group/ElginAPgroup/
Sometimes it's less daunting to nurse in public when you have a whole "gang" of nursing moms to hang out with and support you! :) It's a fun group that gets together at the Centre to swim, meets at parks or farmer's markets, library, etc. and has kids of all ages. We're planning a swap meet for baby/kid items, etc as well!
Luckily IL is a great state to breastfeed in public because there are laws that prevent someone from asking you to leave- you can breastfeed any place in public that you are otherwise authorized to be, AND there is an enforcement provision, which means it is actually punishable for someone to ask you to leave (they can be fined, etc). You might know this already, but it's always nice to remember and some other moms who read this may not be aware. You can visit the La Leche League website for details for any state's laws on breastfeeding in public.
Hope this helps! Luckily spring is in the air, so hopefully cabin fever is almost over :)
M.